Electric machine tools such as drill hammers, circular saws, angle grinders, or the like are often supplied with voltage with the aid of a rechargeable battery. The rechargeable batteries are generally configured in such a way that they may be connected to the machine tool and also detached again. The detachable connection between the rechargeable battery and the machine tool is used, among other things, to recharge a rechargeable battery, which has become depleted due to use of the machine tool, with voltage via a rechargeable battery charging device (also referred to as a rechargeable battery charger, or charger). After the rechargeable battery has been returned to a charged state with the aid of the charger, the rechargeable battery may be reconnected to the machine tool in order to once again supply it with voltage. The rechargeable battery undergoes high stress due to continued use and in particular due to frequent charging, so that after a certain period of time it no longer has its original capacity. Regularly replacing a highly stressed rechargeable battery with a new, more powerful battery is not an uncommon measure. However, since the machine tool and the charger do not necessarily also have to be replaced along with the rechargeable battery, the problem often arises that the new rechargeable battery is not identical to the old, i.e., original, rechargeable battery. As the result of development measures, it is possible that the new rechargeable battery includes a new electromechanical interface device which, although it is compatible with the machine tool, is incompatible with the original charger.
In addition, it is possible that, as the result of such development measures for the rechargeable battery charger, a new charger that is intended to replace the original charger due to signs of wear is not compatible with an older rechargeable battery.
This may result in an incompatibility problem between the rechargeable battery and the charger.